MP11-05 OUTCOMES WITH MINIMALLY INVASIVE RETROPERITONEAL LYMPH NODE DISSECTION (MI-RPLND) AND SINGLE DOSE CARBOPLATIN IN CLINICAL STAGE 2 SEMINOMA

Abstract

INTRODUCTION AND OBJECTIVE: Standard treatment of stage 2 seminoma is usually chemotherapy with 3 cycles of bleomycin, etoposide and cis-platinum(BEP) or 4 cycles of EP. Previous reports with limited follow-up have suggested RPLND either alone or in combination with adjuvant carboplatin as potential alternative options with low volume stage 2 disease. We report our extended experience and follow-up with MI-RPLND in combination with a single dose of adjuvant carboplatin in patients with clinical stage(CS) 2a seminoma. METHODS: From 01/2013-07/2019 40 patients with CS 2a seminoma (17 right, 23 left) underwent MI-RPLND (laparoscopic and robotic) at our tertiary specialist testicular cancer centre. Modified unilateral templates with excision of the gonadal lymphovascular pedicle were performed. A single dose of carboplatin (AUC 7) was administered to patients with histological verification of nodal involvement. Standard post-operative outcomes including length of stay, Clavien-Dindo complications and pathological staging were recorded. All patients remain under our care with a standard surveillance protocol including cross-sectional imaging to monitor for disease recurrence. RESULTS: Median and mean post-operative stay was 1 and 1.5 days. One patient required conversion to open surgery, 1 patient developed an ileus and another a chest infection. Clavien Dindo 1 complications occurred in 5 patients. Median and mean post-operative stay was 1 and 1.4 days. Ejaculation was preserved in all cases. Three patients were downstaged to pN0, with enlarged nodes showing reactive chamnges only, and received no further treatment following surgery. Pathological stage 2 disease was confirmed in the remaining cases who all received adjuvant chemotherapy. In 2 cases nodal disease also contained embryonal carcinoma despite pure seminoma in the testis. These cases received adjuvant BEP. No chemotherapy related complications occurred. Median follow-up is 38 months(3-82 months) with now 25 patients > 3 years since treatment. Only 1 patient has relapsed – with an out of field recurrence at 18 months. This patient was treated with 3 cycles of BEP and remains disease free 20 months later. CONCLUSIONS: MI-RPLND in combination with a single cycle of carboplatin appears a safe option in CS 2a seminoma. This approach avoids inappropriate toxic systemic therapy in a subset of patients clinically overstaged on cross-sectional imaging. Adjuvant carboplatin appears to reduce the risk of relapse compared to that reported in preliminary series of RPLND alone for CS 2a seminoma. Source of Funding: Nil